Mold-form.



M. BLUMENTHAL.

' MOLD FORM.

APPLICATION FILED MAR- |9| 1917.

1,238,384.. Patented Aug. 28, 1917.

5 b If; 2.

nve'wtoz Maurice filament/mt,

one of my UNITED STATES PATENT orator..-

MAURICE BLUMENTHAL, 0F BRQOK LYN, NEW YORK.

MOLD-FORM.

Specification of Letters Patent.

. Application filed March 19, 1917. Serial No. 155,658.

conduits in or of cement, concrete or similar material, and theobject'thereof is to provide an improved mold form of the class and forthe purpose specified whereby conduits Of the class specified andintended for any desired purpose may be quickly, economically and easilyformed or constructed, and with this and other objects in View theinvention consists in a mold form or forms of the class specified,constructed and adapted to. be used as hereinafter described andclaimed.

The invention is fully disclosed in the fol lowing specification, ofwhich the accompanying drawing forms apart, in which the' separate partsof my improvement are designated by suitable reference characters ineach of the views, and in which Figure ,l is a longitudinal sectionalview showing one step in the process of using my improved mold form orforms in making concrete conduits; i

Fig. 2 a similar view showing another step of said process;

Fig. 3 a section on the line 33 of Fig. 1;

Fig. '4 a sectional longitudinal view of proved mold forms;

Fig. 5 a section on the line 5'5 of Fig. i v

Fig. 6 a view similar to Fig. 5 but-showing a modification.

In the practice of my invention, I provide a mold form (1 shown in Figs.1, 5 and 6, and which consists of a metal tube of any desired lengthandany preferred transverse dimensions, and which is made up of -twosimilar opposite longitudinal parts a and two other similar longitudinalparts a and'the parts a are tapered from one end a of the tube to theother end a of the tube, and the parts a are similarly tapered in theopposite direction, and the parts a are rigscrewed into the parts-a -tosetor become hard Patented Aug. 2s, 1.917.

idly connected by transverse brace or other I members a, in any desiredmanner, to form what- I call a wedge or key member a The side portionsor of the wedge member a and the corresponding longitudinal side membersa of the tubular form are preferably connected as shown in Fig. 5, inwhich the side edge portions of the parts a abut against the'side edgeportions of the parts a and the parts a are provided at their oppositeends with lugs or cars a which overlap the parts a and through a whichare and whereby the by the parts a of the tubular form are which arepassed screws wedge member a formed and the parts a rigidly connected. v

In Figs. 1, 2, and 3 I haveindicated a process of using two of myimproved mold forms in making conduits in'cement, concrete and similarmaterial, or in making concrete or cement conduits of the class aspecified, and in said figuresI have also shown at b a section of earthor street in which is dug or formed a trench and, in the practice of myinvention, trench a mold box 0 preferably consisting down, and set upagain for use, whenever deslred.

, ,The end portions 0 and c of the mold box 0 are provided withapertures 0 and the form or forms a are passed through said mold box andthrough said apertures,- as shown in Fig. 1, after which concrete orsimilar material 5 is poured into the mold box, and conduits c are.formed in the concrete, andwhen this concrete has had'time or partiallyso, the wedge member or members a of the forms are drawn out in thedirection of the arrow 00, the screws a havingbeen first withdrawn afterwhich the parts 11 of the forms may be easily taken out as will bereadily understood, after which the parts a of the forms are againconnected and the end portions a thereof are inserted into the conduitsc in the section of concrete first built up, after which the box 0 isplaced in position with: the exception of the end portion 0 thereof, andas indicated in Fig. 2, afterlgwhich said mold box is again filled inwith cQncrete, and

I place in the of side members 0 and end members 0 and .0", and theparts of the mold box may be the conduits are intended, and conduitsmade in this manner may be used as electric cable or wire conduits, oras sewer or drainage conduits, or for any other desired purpose.

In order to be able to pull out the wedge or key member a of the form,as hereinbe fore described, any suitable pulling device or means may beconnected with one of the transverse hr cs members a, or I may form inthe larger end portions of the parts a of the wedge or key member holes(1 with which may be connected any suitable device for performing saidoperation.

In Fig. 6 of the accompanying drawing, I

have shown a modified construction of the mold form a 1n which theseparate parts a and a are abutted and provided with an interlockingrabbet groove construction 6, and with this exception theconstruction-and operation will be the same as that shown in Figs. 4 and5, and one of the parts (0*, the bottom part when the mold form or formsare in use, is provided with a longitudinal rib or fin portion f bywhich a draining groove 9 is formed in the bottom of the conduit orconduits c,

Although I have shown and described my improved mold form as circular inform in cross section, it will be understood that this cross sectionalshape is not absolutely necessary, and other shapes or forms maybeemployed, and changes in and modifications of the constructionherein'described may be .made, within the scope of the appended1,2ss,ase

transversely to form a wedge or key device and the other oppositelyarranged parts being tapered in the opposite direction.

2. A tubular mold form composed of four separate longitudinal parts, ofwhich two oppositely arranged carts are tapered from one end to theolirer and connected to form a wedge or key device and the otheroppositely arranged parts being tapered in the opposite direction, saidparts being detachably connected.

3. A tubular mold form of the class specified, composed of fourlongitudinal similar parts, two of which are tapered from one end of themold device to the other and the othertwo tapered in the oppositedirection, one of said parts being provided on the outer side thereofwith a longitudinal rib or fin.

- 4. A tubular mold device composed of four similar longitudinal parts,of which two opposite parts are tapered from one end to the other of themold device and connected to'form a key or wedge, the other two partsbeing tapered in the opposite direction and all of said parts beingdetachably connected and one of said arts being provided with alongitudinal lo or fin on the outer side thereof.

In testimony that I claim the foregoing 'as my invention I have signedmy name in presence of the subscribing witnesses this 10th day of March1917.

' MAURICE BLIEIENTHAL. Witnesses:

C. E. MULREANY, H. C. THOMPSON.

